P0601: How to Diagnose & Fix — Internal Control Module Memory Check Sum Error
3 vehicles · 3 makes · $300-$1,500 repair
How to diagnose and fix P0601: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Jeep Grand Cherokee · 1999–2004
The WJ PCM (engine computer) can develop internal faults — often heat/temperature-related micro-cracks or solder failures — that cause intermittent stalling, hard-to-diagnose no-starts and driveability problems that come and go with ambient temperature. A well-known WJ case: a 2000 4.7L stalled only when outside air exceeded ~60F; a rebuilt/replaced PCM cured it after many other parts were replaced in vain.
Common Symptoms
- Intermittent stalling, often correlated with heat/warm weather
- Crank but no-start that comes and goes
- Multiple unrelated sensor codes
- Driveability that improves when cold
- Repairs of individual sensors don't resolve it
How to Fix
Diagnose by elimination after CKP, fuel pump, and grounds are ruled out. Options: send the PCM for bench repair (specialists like Circuit Board Medics), or install a remanufactured PCM programmed to the vehicle's VIN and SKIM/immobilizer. Any replacement PCM must be VIN-programmed to run. Inspect PCM connectors/pins for corrosion first.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- UpFix repair-and-return service for the original WJ PCMOEMUpFix 46855
Bench repair of the vehicle's original PCM only after vehicle-side diagnosis confirms an internal module fault covered by the service Fitment/availability: SKU 46855 describes a repair-and-return service for 1996-2004 Grand Cherokee 4.0L…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (2)
Hyundai Creta · 2020–2023
The 1.4L turbo-petrol SU2 Creta's 7-speed dry dual-clutch transmission has multiple well-documented failures in Indian stop-and-go traffic: clutch actuator failure (logged as DTC P060194), the gearbox refusing to engage odd-numbered gears until restart, transmission-overheat warnings in crawling traffic, and judder or delayed engagement from standstill. Team-BHP ownership threads document cars failing within months of delivery and failing again a year after dealer repairs, with Hyundai handling cases reactively rather than via recall. Out-of-warranty repairs are expensive — a full gearbox replacement runs roughly INR 80,000 to over 1.2 lakh.
Common Symptoms
- Transmission hot / overheating warning in slow traffic
- Judder or hesitation when accelerating from a stop
- Odd-numbered gears not engaging until engine restart
- Check engine light with powertrain error message on the cluster
- Sudden loss of drive / limp mode
How to Fix
Dealers replace the failed clutch actuator or clutch pack (free under warranty); a destroyed transmission requires complete DCT replacement. Owners mitigate risk by avoiding prolonged clutch-slip situations (crawling in traffic or holding the car on inclines with throttle) and extending the powertrain warranty.
Sources for this issue (6)
- 6-month old Hyundai Creta 1.4 DCT develops powertrain failure (EDIT: Problems continue even after 2 years) — Team-BHP thread #237754forum
- DCT failure on my 2020 Hyundai Creta SUV — Team-BHPforum
- DCT on my Creta fails yet again, just a year after Hyundai repaired it — Team-BHPforum
- Used Hyundai Creta: Top Hidden Costs (DCT replacement ₹80k–1.2L, overheat warnings in traffic) — Cars24article
- DCT issues in a brand new 2021 Hyundai Creta 1.4L — Team-BHPforum
- Serious gearbox issue in my Kia Seltos DCT (same 1.4 T-GDI 7DCT) — Team-BHPforum
Chrysler Prowler · 1997–2002
The engine PCM (Powertrain Control Module) suffers an internal memory-chip failure that sets code P0601 'Internal Control Module Check-Sum Error' and illuminates the Check Engine Light, which also causes the car to fail most state inspections. Because the Prowler's PCM is a low-volume, long-out-of-production unit, replacement is a documented ownership headache.
Common Symptoms
- Check Engine Light on
- P0601 stored code
- Fails state inspection
How to Fix
The internal chip failure can often be repaired and re-flashed by specialists rather than scrapping the unit; owners are directed to Prowler-specific PCM repair/reprogramming services (e.g., BGPerformance) or to buy a refurbished, VIN-programmed plug-and-play PCM.
Sources for this issue (2)
- The Complete Plymouth Prowler - The Prowler Storespecialist-vendor-guide
- Chrysler 300M Enthusiasts Club (forum thread, April 2024)owner-forum
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P0601 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0601 mean?
P0601 stands for "Internal Control Module Memory Check Sum Error." The control module ran an internal self-check (checksum) on its memory and the calculated value did not match the stored value, indicating corrupted or failed internal memory. It is an internal module integrity fault.
What are the most common causes of P0601?
The most common causes of P0601 are: Corrupted or failed internal PCM/ECM memory, Faulty/aborted software reflash or programming, Low or unstable battery/system voltage during operation, Corroded PCM ground or power connectors, Defective control module. The specific cause varies by vehicle.
How much does it cost to fix P0601?
Repair costs for P0601 range from $300 to $1,500, depending on the vehicle and root cause.
Which vehicles are affected by P0601?
Au7o has documented P0601 across 3 vehicle models from 3 manufacturers: Chrysler, Hyundai, Jeep.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.